Auxiliary speed control mechanism for knitting machines



March 4, 1952 p, Ems-raw 2,587,816

AUXILIARY SPEED CONTROL MECHANISM FOR KNITTING MACHINES Filed March 23,1950 5 Sheets-Sheet 1 IN V EN TOR.

PAUL w. BR/S TOW March 4, 1952 P. w. BRlSTOW AUXILIARY SPEED CONTROLMECHANISM FOR KNITTING MACHINES Filed March 25, 1950 3 Sheets-Sheet 2INVENTOR. PAUL W BRISTOW was.

ATTORNE S.

March 4, 1952 p w, ms-row 2,587,816

AUXILIARY SPEED CONTROL MECHANISM FOR KNITTING MACHINES Filed March 25,1950 3 Sheets-Sheet 3 na 2 F/G. 9.

v V INVENTOR. PAUL W. BR/STO BY dw y ATTORNEYS.

Patented Mar. 4, 1952 AUXILIARY SPEED CONTROL MECHANISM. FOR KNITTINGMACHINES Paul W. Bristow, Laconia, N. H., assignor to Scott & Williams,Incorporated, Laconia, N. H.,. a corporation of MassachusettsApplication March 23, 1950, Serial No. 151,465

8 Claims.

This invention relates to an auxiliary speed control mechanism forknitting machines designed to save moves of a main pattern drum of themachine while at the same time providing for necessary speed changes.

In knitting machines intended for the production of elaborate types ofhosiery there is the necessity for making the most out of the availablesteps of the main pattern drum. In order to speed up production it isdesirable to operate the knitting machine at high speeds whenever suchspeeds are permissible for straight away knitting. Accordingly, themachines are provided with speed control cams which will shift the drivefrom low speed to high speed and vice versa in the production of astocking. Assuming that the machine is operating at high speed and thatit is required to operate at low speed for the changes necessary toeffect some subsequent knitting operation, it is necessary that themachine should be slowed down before the changes are made; in otherwords, it is not generally permissible to effect the slowing down of themachine simultaneously with the making of the changes. If the speedcontrol cams are secured to and moved with the pattern drum it isevident that the last requirement makes necessary the use of two stepsof the drum in order to effect the change, the first step beingnecessary to provide the slowing down of the machine and the second forthe actual effecting of the requiring change. If, for example, in theknitting of a complete stocking four slow downs from high speed arerequired there are correspondingly used four steps of the main patterndrum which might otherwise be used. In accordance with the presentinvention these steps of the main drum which would ordinarily be usedfor the purpose of slowing down the machine are saved with the resultthat they may be used, if desired, for other purposes. The result isthat without increasing the steps of the main drum more elaborateknitting may be produced. 7

In order to make clear the particular advantages of the invention theremay be here and hereafter considered the application of the inventionto. a machine of superposed cylinder type capable of knitting broadribstockings and involving the wrapping of. panels of needles between broadribs to secure clocks or other pattern formations. A typical sequence ofknitting in such a machine for the formation of an elaborate stockingwith the attainment of high speeds of knitting to increase productionwhenever such high speeds are permissible may be described as follows:

Starting with the looping rounds after completion of a toe, theselooping rounds may be produced during high speed operation of themachine. Following their completion the machine must be slowed down forthe transfer of needles for the production of the first welt. The slowspeed operation will then continue during the knit-ting of the firstwelt, during the formation of the press-01f draw thread, and during theknitting of the regular welt. The last knitting of the regular welt isthen followed by the formation of a 1 x 1 rib top which may be knittedat high speed. However, the machine must again be slowed down prior tothe transfer of needles to produce broad rib knitting. Afterthistransfer is effected the machine may again resume high speed operationfor the knitting of broad rib fabric at the top of the leg precedingwrapping, for example for the formation of a clock Before wrapping isstarted the machine must again pass to low speed operation which iscontinued through the wrapping, the half-round transfer of needlesbefore the heel and the formation of the heel. If clocks are providedthere is then a continuation of wrapping in the foot and the low speedoperation is continued through such wrapping. When the wrapping iscompleted, however, high speed operation may again be resumed for completion of the foot and low speed operation resumed'prior to thetransfer which occurs before the formation of the advanced toe. Lowspeed operation is then continued through the formation of the toe anduntil the beginning of the looping rounds.

It will be noted that in the foregoing there are four necessarytransitions from high speed to low speed operation and these transitionsmust be completed prior to the operations which follow including, forexample, transfers of needles between the cylinders and beginning ofwrapping.

Since in the formation of such an elaborate stocking a large number ofmoves of the main drum are required it is advantageous to conserve thesemoves as far as possible. In accordance with the present invention anauxiliary speed control mechanism is provided associated with the maindrum but of such nature that it performs the operations of slowing downthe machine prior to the moves of the drum to positions requiring theslow operation. These results are accomplished without correspondingmoves of the main drum.

The broad object of the invention will become apparent from theforegoing and consists of the attainment of the advantageous resultsindicated. The Securing of this broad object as well as other objectsparticularly relating to details of conindicated at i.

Figure 2. the drum 2 is the ratchet l2 which is provided with teethdefined by notches l4 engageable by the nose I6 of a pawl l8 pivoted toan arm 28 .which is rocked in conventional fashion in time partillustrated in Figure 1, this section being on the vertical planeindicated by the traces shown at 2-2 in Figures 3 and 4;

Figure 3 is a vertical section taken on the plane the trace of which isindicated at 33 in Figure 2;

Figure 4 is a section taken on the plane indicated at 3-4 in Figure 2;

Figure is a fragmentary perspective View serving for the clearerillustration of certain of the parts shown in Figure 1; and

Figures 6, '7, 8 and 9 are diagrammatic figures showing the sequence ofoperations involved in speed change.

At 2 there is indicated the main cam drum of the machine carryingcontrolling cams such as In some machines this main cam drum actuallyconsists of two drums, one a clutch control drum and the other aso-called .quality drum. While these drums rotate together in unisonthey may be made relatively angularly adjustable so as to provide fineadjustment of the timing of the quality steps with respect to the clutchchanges from reciprocation to rotation and vice versa. The drum 2 isillustrated as provided with a hollow hub 6 pinned as indicated at IE]to a shaft 8 having a left-hand bearing which is not illustrated inSecured for angular adjustment to with the needle cylinders. It may beassumed,

as is usual, that the lever 20 has a complete stroke for every tworevolutions of the needle cylinders. The pawl i3 is provided with alaterally extendling pin 22 which overlies an arm 24 carried by a hub 26pivoted on a fixed pin which hub also carries a follower 28 engageableby lugs 38 on .the main pattern chain 32 carried by the sprocket wheel34.

To this sprocket wheel 34 there is secured a ratchet 36 which isadvanced in general the distance of one full link for eachtwo-revolutions of the needle cylinder by a pawl Mounted on the hub 38supported by a lever 40. portion of the ratchet 36 for free rotationrelative to ratchet 36 and the sprocket wheel 34 is a masking ratchet d2also engageable by the pawl 38 and provided with a relieved space in itscircumference to permit the pawl 38 to engage the ratchet 33, thisratchet being disengaged by ,yentional and need not be more fullyreferred to since their constructions and operation are fully describedin my prior Patent 2,436,468, dated February 24, 1948. As will becomemore evident hereafter, with reference to said patent, the parts so'farindicated operate in their usual fashions.

The sprocket wheel as is journalled on the sleeve portion 33 of a member44 secured in the viewed in Figure machine frame. The sleeve 63 providesa hearing for a shaft 46 which at its left-hand end is journalled in thebore 50 of the drum 2. A spacer 48 surrounding the shaft 35 isinterposed between the sprocket wheel 34 and the hub member 52 to whichthere is secured by screws 54 the speed control rack wheel 55 whichcarries at its periphery a series of bluff members 58 which, as

will appear hereafter, are acted upon by the nose l5 of pawl 18. The hub52 is secured to shaft 48 by a set screw 59. The rack wheel 56 isprovided with an opening located to the right, as 3 of a spoke 6E! andinto the space thus provided there projects an eccentric washer 62secured by a screw 65 to the ratchet l2. As will be evident adjustmentof the eccentric washer serves for the fine adjustment of the operatingrelationships between the ratchet I2 and the rack wheel 56.

A hub 66 is keyed tothe shaft 45 and secured against lengthwise movementrelative to the shaft by a set screw 51. A left-hand extension 68 ofthis hub as viewed in Figure 2 is surrounded by a brake band 69 which isarranged to engage a pin 70 secured to the frame to maintain itstationary so that it imposes a drag on the rotation of the hub 66 andshaft 5. An outwardly extending lug F2 on hub 66 has threadedtherethrough a screw is arranged to abut a lug '56 on a cam carrier itwhich is slotted at Bil for the passage of screws 82 threaded into thehub 66. This arrangement provides for fine angular adjustment of thecarrier '53 with respect to the hub 6%. A group of cams 8e are bolted tothe periphery of the carrier 78 and between these cams there aredepressions 38, 88, 9%! and 92 which will be referred to hereafter. Theearns 84 are arranged to act upon a pin fit carried by a lever 95 whichis connected by link 98 to the lever lei! of a belt shifting arrangementincluding the fork members 562 for control of a belt which runs from adriving pulley to the idler pulley I94, the low speed puiley 166 or thehigh speed pulley it. This belt shifting mechanism is conventional andneed not be further described.

' As is usual it is associated with manual belt shifting means and withan arrangement for shifting the belt to the idle pulley under control ofa stop motion device. The machine is provided with the usualarrangements, not shown, whereby under control of the clutch cams thedrive may selectively rotate or reciprocate the needle cylinders.

The operation of the described mechanism may now be considered.

It will be evident that in the absence of blufis 58 within the range ofaction of the pawl nose I6 the pawl i8 would effect advance of thepattern drum 2 in conventional fashion as controlled by the lugs 30 onthe pattern chain 32, the nose I6 engaging to drive the drum the notchesI i in the ratchet I2. I

Assume now that the machine is in a phase of high speed operation withthe pin 94'within one of the spaces 8'6, 83, 9G or 92 and that a changeof control is to occur which requires, at the time of the change, lowspeed operation of the ma chine. By reason of the action of theeccentric washer E2 on the surface of the spoke 60, the speed controlrack wheel will have been dragged about as the drum 2 is stepped so thatthese two elements will, in general, have been moving in unison. In themovement of the drum 2 preceding that which is to control the changerequiring low speed operation, the rack wheel 56 and ratchet I2 will bepositioned as indicated in Fignormally be the next notch to be engagedby the nose I6 of the pawl. The bluff 58 is provided with a tooth III!which extends above a sloping edge 2, the left-hand end of whichadjacent to the tooth is at a diameterexceeding the diameter of theperiphery of the ratchet I 2. This edge II2 terminates at a shoulder IMwhich drops below the periphery of the ratchet I2.

Figure 6 illustrates the pawl nose I 6 at the beginning of its strokewhenit has been positioned by the action of a lug 36 on the patternchain to i The beginning of this have an active stroke. stroke will betimed to occur two cylinder revolutions before the change required ofthe pattern drum. As will be evident from Figures 6 and 7 the stroke ofthe pawl will advance the bluff 58 but, though the nose I6 engages thetooth III! it will be prevented from engaging in the notch MA by reasonof the fact that it rests on the bluff edge I I2 beyond the periphery ofratchet I2. Accordingly at the end of its forward stroke the parts willbe in the position illustrated in Figure '7. The advance of the blufiwill have rotated the earns 84 so that the pin 94 will be movedoutwardly to shift the belt to the low speed pulley I 96. The machinewill accordingly slow down and will have the period of approximately tworevolutions of the needle cylinders to reach slow speed before the drum2 is advanced as will now be described.

The pawl after withdrawing to the beginning of i its next stroke willoccupy the position illustrated in Figure 8 in which it enters the notchMA. A

second lug 30 on the next succeeding chain link that of Figure 9 it willbe evident that theratchet I2 will be advanced one step to move the maindrum to a position to effect the change of control which required thelow speed operation. During the forward movement the nose I6 will engagethe step [I4 of bluff 58 and will advance the bluff to the positionrelative to the ratchet indicated in Figure 9. Thereafter the bluffswill be carried about in usual fashion by the main drum through theaction of eccentric 62 on the spoke 6D, the brake 69 retarding freemovement of the bluffs and their associated parts so that when the nextbluff reaches operative position it will be properly located withrespect to another notch I4 of the ratchet.

From the foregoing it will be seen that the objects of the invention areaccomplished in that the shift from high speed to low speed operationdoes not require one of the steps of the pattern drum, the only step ofthe pattern drum involved being that which controls the machine elementsrequiring the low speed of operation as a condition precedent to theiroccurrence.

It will be evident that these transitions from high to low speed may beproduced wherever required, the cam interruptions at 88, 88, 90 and 92being provided, for example, to correspond to the transitions describedspecifically above with reference to the knitting of a stocking on asuperposed cylinder machine with wrapping of clocks;

Transitions from low speed :to high speed operation may, in general, bemade simultaneously with advances of the pattern drum and need notinvolve the special actions described. It will be evident, however, thatif necessarysuch changes may also involve the use of the bluffs. The caminterruptions may be of any suitable extent corresponding to theduration of high speedoperation.

It will, of course, be evident that the invention is of quite generalapplication to various types of knitting machines and it is therefore tobe understood that the invention is not to-be regarded as limited exceptas required by the following claims.

What is claimed is:

v1. In a knitting machine, a pattern device, a cyclically operatingelement for advancing asaid pattern device step by step, meanscontrolling the occurrence of active cycles of said element, means forcontrolling'the speed of the knitting machine, and means for effectingin one active cycle of said element an advance of said :speedcontrolling means to change the speed of the knitting machine while thepattern device remains stationary, and in a subsequent active cycle ofsaid element an advance of said pattern device.

2. In a knitting machine, a pattern device, a ratchet connected to saidpattern device, a cyclically operating pawl engaging said ratchet toadvance said pattern device step by step, means effective to control thepatho'f movement of said pawl thereby to control the occurrence ofactive and inactive cycles of said pawl, means for controlling the speedof the knitting machine including a cam device, and racking memberssecured 'to said cam device and engageable by said pawl during activecycles thereof, said racking members having guard portions which, whenengaged by said pawl, prevent engagement of said ratchet by the pawl,and said cam device being mounted to be advanced with said patterndevice in movements thereof, the racking members being so arrangedrelative to said ratchet that in one active cycle of said pawl the camdevice is advanced to change the speed of the knitting machine while thepattern device remains stationary, and in a subsequent active cycle ofsaid pawl the pattern device is advanced.

3. In a knitting machine, a pattern device, a ratchet connected to saidpattern device, a cyclically operating pawl engaging said ratchet toadvance said pattern device step by step, means effective to control thepath of movement of said pawl thereby to control the occurrence ofactive and inactive cycles of said pawl, means for controlling the speedof the knitting machine including a cam device, and racking memberssecured to said cam device and engageable by said pawl during activecycles thereof, said racking members having guard portions which, whenengaged by said pawl, prevent engagement of said ratchet by the pawl,and said cam device being mounted to be advanced with said patterndevice in movements thereof, the racking members being so arrangedrelative to said ratchet that in one active cycle of said pawl the camdevice is advanced to change the speed of the knitting machine while thepattern device remains stationary, and in the next active cycle of saidpawl the pattern device is advanced.

4. In a knitting machine, a pattern drum, a ratchet connected to saidpattern drum to rotate therewith, a cyclically operating pawl engagingsaid ratchet :to advance said pattern drum step by step, means effectiveto control the path of movement of said pawl thereby to control the-occurrence of active and inactive cycles of said pawl, means for.controlling the speed of the knitting machine including a cam devicemounted coaxially with said pattern drum, and racking members secured tosaid cam device and engageable by said pawl during active cyclesthereof, said racking members having guard portions which, when engagedby said pawl, prevent engagement of said ratchet by the pawl, and saidcam device being mounted to be advanced with said pattern drum inmovements thereof, the racking members being so arranged relative tosaid ratchet that in one active cycle of said pawl *the 'cam deviceis'advancedto change the speed of .the knitting machine while thepattern drum remains stationary, and in a subsequent active cycle ofsaid pawl the pattern drum is advanced.

5. In a knitting machine, a pattern drum, a ratchet connected to saidpatternv drum to rotate therewith, a cyclically operating pawl engagingsaid ratchet to advance said pattern drum step by step, means effectiveto control they path of movement of said pawl thereby to control theoccurrence of active and inactive cycles of said pawl, means forcontrolling the speed of the knitting machine including a cam devicemounted coaxially with said pattern drum, and racking members secured tosaid cam device and engageable by said pawl during active cyclesthereof, said racking members having guard portions which, when engagedby said pawl, prevent engagement of said ratchet by the pawl, and saidcamdevice being mounted to be advanced with said pattern drum inmovements thereof, the racking members being so arranged relative tosaid ratchet that in one active cycle of said pawl the cam device' isadvanced to change the speedof the knitting machine while the patterndrum remains stationary, and in the next active cycle of said pawl thepattern drum is advanced.

6. In a knitting machine, a pattern drum, a ratchet connected to saidpattern drum to rotate therewith, a cyclically operating pawl engagingsaid ratchet to advance said pattern drum step --by step, meanscomprising a main pattern chain effective to control the path ofmovement of said pawl thereby to control the occurrence of active andinactive cycles of said pawl, means for controlling the speed of theknitting machine including a cam device mounted coaxially with saidpattern drum, and racking members secured to said cam device andengageable by said pawl --during active cycles thereof, said rackingmembers having guard portions which, when engaged by said pawl, preventengagement of said ratchet by the pawl, and said cam device beingmounted to be advanced with said pattern drum in movements thereof, theracking members being so arranged relative to said ratchet that in oneactive cycle of said pawl the cam device is advanced to change the speedof the knitting machine while the pattern drum remains stationary, andin a subsequent active cycle of said pawl the pattern drum is advanced.

7. In a knitting machine, a pattern drum, a ratchet connected to saidpattern drum to rotate therewith, a cyclically operating pawl engagingsaid ratchet to advance said pattern drum step by step, means comprisinga main pattern chain effective to control the path of movement of saidpawl thereby to control the occurrence of active and inactive cycles ofsaid pawl, means for controlling the speed of the knitting machineincluding a cam device mounted coaxially with said pattern drum, andracking members secured to said cam device and engageable by saidlpawlduring active cycles thereof, said racking members having guard portionswhich, when engaged by said pawl, prevent engagement of said ratchet bythe pawl, and said cam device being mounted to be advanced with saidpattern drum in movements thereof, the racking members being so arrangedrelative to said ratchet that in one active cycle of said pawl "the camdevice is advanced to change the speed controlling means to reduce thespeed of the knitting-machine'while the pattern device remainsstationary, and in a subsequent active cycle of said element an advanceof said pattern device.

PAUL W. BRISTOW.

REFERENCES CITED The following references are of record in the file ofthis patent:

'UNITED STATES PATENTS Number Name Date St. Pierre Nov. 19, 1946

